Graduate PD code yields two different knot diagrams

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SUMMARY

The PD code [(2, 3, 1, 4), (4, 1, 3, 2)] corresponds to a unique link diagram, specifically a Hopf link, rather than a knot diagram. The discussion clarifies that while a PD code can yield multiple link diagrams, it does not produce multiple knot diagrams. The confusion arises from the visual similarity of the diagrams, which appear as interconnected rings, leading to the misconception that they represent knots. The Hopf link consists of two linked unknots, confirming its validity as a link diagram.

PREREQUISITES
  • Understanding of PD (Plane Diagram) codes
  • Familiarity with knot theory terminology
  • Knowledge of link diagrams versus knot diagrams
  • Basic concepts of topology related to knots and links
NEXT STEPS
  • Study the properties of Hopf links in knot theory
  • Explore the implications of PD codes in knot and link diagrams
  • Learn about the classification of knots using the Rolfsen Knot Table
  • Investigate the relationship between unknots and linked structures in topology
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Mathematicians, knot theorists, and topology enthusiasts interested in the distinctions between knots and links, as well as those studying the applications of PD codes in knot diagrams.

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TL;DR
The same PD code seems to yield two different knot diagrams of the Hopf link
The PD code [(2, 3, 1, 4), (4, 1, 3, 2)] seems to map to a non-unique knot diagram. I can describe the following two Hopf links with different orientations with this same PD code. As I understand it, while a link diagram does not have a unique PD code, a given PD code should map to just one knot diagram. Am I missing something?

IMG-6314.jpg
 
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Sorry, the PD code maps to a unique *link* diagram, so the Hopf link is a valid diagram (also, a ring is the unknot so it's still a knot, right? The Hopf link is just two linked unknots)
 
I don't know if it helps, but:

Make half a turn (the least complicated direction) of one of the 4 rings around the horizontal axis.
 

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